<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <script>
        var day = 3;
        switch(day){
            case 1:
                console.log("今天是星期一");
                break;
            case 2:
                console.log("今天是星期二");
                break;
            case 3:
                console.log("今天是星期三");
                break;
            case 4:
                console.log("今天是星期四");
                break;
            case 5:
                console.log("今天是星期五");
                break;
            case 6:
                console.log("今天是星期六");
                break;
            case 7:
                console.log("今天是星期天");
                break;
            default:
                console.log("输入错误");
        }

    </script>
</body>
</html>